Regulators designed for use in pressurized gas lighters generally operate on the principle of passing gas through a compressed filter medium placed upstream of the shut-off plug or washer of the lighter. The filtering medium offers resistance to the flow of gas causing a drop in pressure.
Several materials are currently used for filtering, including plastic fiber matrices, plastic foam and porous plastics. The most common form of construction is one which compresses the filter material between plates during assembly. The effective pressure drop across the regulator can then be further adjusted by compressing or decompressing the filter in order to vary its average pore size.
One of the major problems with such an arrangement is that the characteristics of the filter medium will continue to undergo changes over a period of time, even though there are no mechanical changes in the relationship of the parts. This effect is called "creep" and is particularly troublesome and hard to predict and control with the highly elastic plastics materials of which most regulators are constructed.
The objective of this invention is to alleviate the above problems in the prior art through the provision of a simple and economical regulator means which is efficient in its operation on a constant basis over a long period of time without changing its physical or its operational characteristics. The invention departs from the traditional practice of employing a bulk porous filter medium and in lieu thereof employs a surface effect regulator in which the gas is forced to flow through a multiplicity of interstices of a textured surface element. The resulting pressure regulation is consistent and the problem of "creep", above noted, is entirely absent.
Other features and advantages of the invention will also become apparent during the course of the following description.
To comply with the duty to disclose known prior art under 37 C.F.R. 1.56, the following United States patents and one French patent are made of record herein Nos.:
2,126,991 PA1 3,523,005 PA1 3,533,721 PA1 3,709,462 PA1 3,820,941 PA1 3,859,037 PA1 3,860,385 PA1 3,922,139 PA1 3,036,579 PA1 1,057,471--(French)